This invention relates to a servomechanism for a rotary type flying cutting apparatus.
For example, in a pipe mill or the like, there is employed a reciprocatory cutting system in which a moving pipe is cut by a cutter moving together therewith without stopping the pipe at each cutting operation. In such a case, for accurately cutting the pipe into a predetermined length, it is necessary to make the moving speed of the cutter equal to the travelling speed of the pipe. For this purpose, a servo control is usually employed. In the case where the cutter is moved in parallel with the moving pipe, the servo system can be formed relatively easily.
However, in a rotary type flying cutting apparatus in which a cutter rotating like a rotary saw, is revolved to cut a moving member in a certain rotational angular range of the cutter, it is relatively difficult to make the revolving speed of the cutter equal to the travelling speed of the moving member to be cut. Namely, the member to be cut travels in a straight line but the cutter moves in a circle and the component of movement of the cutter along the straight line is required to be made equal to the travelling speed of the moving member.
One object of this invention is to provide a servomechanism for a rotary type flying cutting apparatus which enables a servo control of the length of a member to be cut.
Another object of this invention is to provide a servomechanism for a rotary type flying cutting apparatus which enables a servo control of length measurement and speed.